1. Field of the Invention
The present invention relates to a position-detecting sensor and more particularly to a position-detecting sensor utilizing magnetism which is provided for detecting position of a moving object such as a rotor, or some other such object which changes its position.
2. Description of the Prior Art
With regard to a position-detecting sensor utilizing magnetism, the sensor described in U.S. Pat. No. 4,319,188 has been proposed. This U.S. patent describes a magnetic sensor comprised of a magnetic recording medium carried on a moving object (rotor) and a magnetic resistance-effect element disposed nearby this magnetic recording medium (hereinafter, referred to as an MR element.).
However, this magnetic sensor does not provide any design against output variation of the magnetic sensor which occurs where the gap between the magnetic recording medium and the MR element varies.
Accordingly, the output of a magnetic sensor varies in accordance with variation in spacing caused by deflecting the center of a rotor or the like. As a result, in a position-detecting sensor with a sine wave output, it is impossible to obtain a correct output conforming to a position, because the peak value of the sine wave varies.